Remove the small rubber cap on the top of the machine. Its about 6mm in diameter.

Remove the small rubber cap on the top of the machine. Its about 6mm in diameter.

−

Unscrew the three phillips head screws that hold the large, black face plate on the left side of the machine.

+

Unscrew the three phillips head screws that hold large, black face plate on the left side of the machine. They are the screws around the perimeter.

Once the needle bar mechanism is visible... Inside the faceplate, remove the black plate that covers the upper half of the needle bar. Remove the screw that holds the needle bar to rotating arm that moves the bar up and down. Use the correct size driver for this last screw, its stiff and can be stripped if you use the incorrect size driver.

Once the needle bar mechanism is visible... Inside the faceplate, remove the black plate that covers the upper half of the needle bar. Remove the screw that holds the needle bar to rotating arm that moves the bar up and down. Use the correct size driver for this last screw, its stiff and can be stripped if you use the incorrect size driver.

The needle bar slides straight up and out of the top of the machine.

The needle bar slides straight up and out of the top of the machine.

+

+

Note that the needle bar has score marks several centimeters above the screw holes. They are visible if you enlarge the image on the right. These are for Needle to Bobbin Hook alignment described in page 6, section 18, of the Manual: [[Media:Juki-ddl-5550-6.pdf]]

Insert the new needle bar with the faceted side facing you and the set screw hole facing right of the sewing machine operator.

Insert the new needle bar with the faceted side facing you and the set screw hole facing right of the sewing machine operator.

−

Tighten the screw on the rotating arm. Replace the black plate. Replace the thread guides (Juki part numbers #229-06309 and #110-18801). Replace the needle (notch facing to the right of the operator). Replace the set screw that holds the needle. Replace the big black faceplate on the side of the machine and the three phillips screws that hold it on.

+

Tighten the screw on the rotating arm. As noted two steps above, you will have to adjust the Needle to Hook relationship as described in the manual section 18.

+

+

Replace the black plate.

+

+

Replace the thread guides (Juki part numbers #229-06309 and #110-18801).

+

+

Replace the needle (notch facing to the right of the operator).

+

+

Replace the set screw that holds the needle.

+

+

Replace the big black faceplate on the side of the machine and the three phillips screws that hold it on.

Its probably a good idea to change the sewing machine oil. This can be a very messy process if you overfill it. It will spill on the floor, so don't overfill it! Use new oil because used oil may contain a tiny amount of water which will eventually rust the mechanism.

Its probably a good idea to change the sewing machine oil. This can be a very messy process if you overfill it. It will spill on the floor, so don't overfill it! Use new oil because used oil may contain a tiny amount of water which will eventually rust the mechanism.

Revision as of 22:12, 22 June 2013

Counter Knife

Description

The Juki 5550-6 has a stationary knife, a moving knife, and a thread guide. If they get dull, you will find that the thread does not cut and a rat's nest can build up in the needle plate. The stationary knife may be resharpened once, but I don't think we have a sharpening stone. Its easiest to replace all three at once. I found our thread guide was broken too. If sewing heavy thread, the knife will only last 3 months. It takes under an hour to replace these parts. Keep the knife area clean by removing the needle plate and blowing compressed air on the knives. This helps a lot.

I bought a pack of all three parts for $18 on eBay. They are Strong H brand and may not be as good as Juki brand parts, but so far (after one day) they are better than the dull knives we had. I searched ebay for Juki 5550-6. Its listed as an 'Undertrimmer Knife Set'. Original Juki parts would cost $38+tax and a trip to Apparel City (I couldn't find Juki brand parts online).

Instructions

Caution! Unplug the machine!

You need a #3 allen wrench and this 1/4 wrench with a 4.5 flathead bit. and a can of compressed air. The small flathead screwdriver used for needle changes (in the grey drawer beneath the Juki) is useful too.

Remove needle plate.

Clean the area with compressed air (use air compressor in the dirty shop if there is no canned air).

Note current adjustment position of the stationary knife... This is how we probably want the new one installed.

The wrench pictured above makes it possible to loosen and tighten these small screws at the tough angle. I found the tools in the dirty shop in the top right drawer. The small wrench was in with the ratchets.

Dab a drop of sewing machine oil on the moving knife with a cotton swab. (I'm not sure if this is needed. It may just attract dirt. Considering the abuse it takes, it's probably a good idea).

Replace all three parts in the reverse order that you removed them. A dab of something sticky (I used solder rosin) on the needle replacement flathead screwdriver can keep the tiny screw captive as you replace it into it's hole.

Last Replaced (log replacement date here)

May 1, 2011 - Chris Murphy

Needle Bar

Description

The Juki 5550-6 has a polished rod that holds the needle with a set screw. The hole that holds the set screw that holds the needle got stripped and then someone made some improvisations instead of fixing the problem by ordering and replacing the part. That wasn't good because we lost the thread guides in the process.

Needle Bar part #22906002

Needle Bar Thread Guide part #229-20805 or alternative part number #110-18801

Needle Bar Thread Guide part #229-06309

Buying

Be sure the new needle bar comes with the set screw as well... or reuse the old one.
Needle Bar, Juki #22906002

Instructions

Caution! Unplug the machine!

You need a large-ish phillips screw driver and several medium and small slotted screw drivers. You also need an egg carton or tray to hold the various parts.

Remove the needle, the set screw that holds the needle, and the thread guides (Juki part numbers #229-06309 and #229-20805 or alternative part number #110-18801)

Remove the small rubber cap on the top of the machine. Its about 6mm in diameter.

Unscrew the three phillips head screws that hold large, black face plate on the left side of the machine. They are the screws around the perimeter.

Once the needle bar mechanism is visible... Inside the faceplate, remove the black plate that covers the upper half of the needle bar. Remove the screw that holds the needle bar to rotating arm that moves the bar up and down. Use the correct size driver for this last screw, its stiff and can be stripped if you use the incorrect size driver.

The needle bar slides straight up and out of the top of the machine.

Note that the needle bar has score marks several centimeters above the screw holes. They are visible if you enlarge the image on the right. These are for Needle to Bobbin Hook alignment described in page 6, section 18, of the Manual: Media:Juki-ddl-5550-6.pdf

Insert the new needle bar with the faceted side facing you and the set screw hole facing right of the sewing machine operator.

Tighten the screw on the rotating arm. As noted two steps above, you will have to adjust the Needle to Hook relationship as described in the manual section 18.

Replace the black plate.

Replace the thread guides (Juki part numbers #229-06309 and #110-18801).

Replace the needle (notch facing to the right of the operator).

Replace the set screw that holds the needle.

Replace the big black faceplate on the side of the machine and the three phillips screws that hold it on.

Its probably a good idea to change the sewing machine oil. This can be a very messy process if you overfill it. It will spill on the floor, so don't overfill it! Use new oil because used oil may contain a tiny amount of water which will eventually rust the mechanism.